1. Field of the Invention
The present invention relates to an automatic vending machine and, more particularly, to an automatic vending machine for performing discount sales so as to sell a plurality of products within the amount of a coin or coins inserted for a single purchase.
2. Description of the Prior Art
Among conventional automatic vending machines for continuously selling a plurality of products within the amount of a coin or coins inserted for a single purchase, a conventional automatic vending machine is described in Japanese patent publication No. 54-42799 wherein products are discounted by a predetermined amount in accordance with the total amount of a coin or coins inserted for a single purchase. Other conventional automatic vending machines are also described in Japanese patent publication No. 59-2075 and Japanese patent disclosure No. 54-87296, wherein products are discounted by a predetermined amount in accordance with a predetermined number of products to be purchased at a single time.
In a conventional automatic vending machine for performing discount sale of products when the number of products exceeds a predetermined number for each purchase, assume that 70 products are discounted by 30 when six products are purchased. In this case, when a customer inserts coins for a total amount of 390 (=70.times.6- 30), six products are to be purchased. However, when the customer inserts coins for a total amount of 400 so as to purchase six products, an outstanding balance is displayed as 50 when the fifth product is purchased. Under this condition, the customer cannot purchase the sixth product, resulting in inconvenience. In a conventional automatic vending machine for performing discount sales of this type, unless coins for the total amount of a nondiscount sale are inserted, products for a discount sale cannot be purchased. Therefore, even if coins amounting to a discount sale amount are inserted, such products cannot be purchased, resulting in inconvenience.